Letter pubs.acs.org/NanoLett
Extended Defects Formation in Nanosecond Laser-Annealed Ion Implanted Silicon Yang Qiu,† Fuccio Cristiano,*,† Karim Huet,‡ Fulvio Mazzamuto,‡ Giuseppe Fisicaro,§ Antonino La Magna,§ Maurice Quillec,∥ Nikolay Cherkashin,⊥ Huiyuan Wang,# Sébastien Duguay,# and Didier Blavette# †
LAAS, CNRS and Université de Toulouse, 7 av. Du Col. Roche, 31400 Toulouse, France Excico, 13-21 Quai des Gresillons, 92230 Gennevilliers, France § CNR-IMM, VIII Strada, I-95121 Catania, Italy ∥ Probion Analysis, 37 rue de Fontenay, 92220 Bagneux, France ⊥ CEMES, CNRS UPR 8011 and Université de Toulouse, 29 rue Jeanne Marvig, 31055 Toulouse, France # Normandie University, GPM, UMR 6634 CNRS, 76801 Saint Etienne du Rouvray, France ‡
ABSTRACT: Damage evolution and dopant distribution during nanosecond laser thermal annealing of ion implanted silicon have been investigated by means of transmission electron microscopy, secondary ion mass spectrometry, and atom probe tomography. Different melting front positions were realized and studied: nonmelt, partial melt, and full melt with respect to the as-implanted dopant profile. In both boron and silicon implanted silicon samples, the most stable form among the observed defects is that of dislocation loops lying close to (001) and with Burgers vector parallel to the [001] direction, instead of conventional {111} dislocation loops or {311} rod-like defects, which are known to be more energetically favorable and are typically observed in ion implanted silicon. The observed results are explained in terms of a possible modification of the defect formation energy induced by the compressive stress developed in the nonmelted regions during laser annealing. KEYWORDS: Laser thermal annealing, extended defects, transmission electron microscopy, secondary ion mass spectrometry, atom probe tomography, ion implantation dislocation loops (DLs)), named hereafter “conventional” defects, have been reported.5,7 {111} DLs exhibit Burgers vectors lying along ⟨111⟩ directions (faulted DLs) or ⟨110⟩ directions (perfect DLs). In addition, “unconventional” DLs with the (001) habit plane and Burgers vector lying along the [001] direction have also been observed in the past in the presence of high concentrations of boron (above its solid solubility in Si).8−10 These loops are formed in the early stages (i.e., after few seconds anneal at low temperature) of boron and Si interstitials coprecipitation and are known as “large” boron interstitial clusters (BICs). In contrast, the much shorter duration time of excimer laser annealing (